#include <bits/stdc++.h>
using namespace std;

#define int int64_t
#define endl "\n"
using PII = pair<int, int>;
using TII = tuple<int, int, int>;
#define FOR(i, a, b) for (int i = (int)(a); i <= (int)(b); i++)
#define FOR2(i, a, b, c) for (int i = (int)(a); i <= (int)(b); i += c)
#define FORD(i, b, a) for (int i = (int)(a); i >= (int)(b); i--)
#define FORD2(i, b, a, c) for (int i = (int)(a); i >= (int)(b); i -= c)
#define BSI basic_string<int>
#define BSPI basic_string<PII>
#define ALL(a) a.begin(), a.end()
#define RALL(a) a.rbegin(), a.rend()
#define VI vector<int>
#define VII vector<vector<int>>
#define VPII vector<PII>
#define lowbit(x) ((x)&(-x))
#define RE return;
#define RET return true;
#define REF return false;
#define Yes cout << "Yes" << endl;
#define YES cout << "YES" << endl;
#define No cout << "No" << endl;
#define NO cout << "NO" << endl;
#define pb push_back
#define fi first
#define se second
#define sz size()
constexpr int N = 2e5 + 10;
constexpr int mod = 998244353;

int __FAST_IO__ = [](){
    ios::sync_with_stdio(0), cin.tie(0);
    cout.tie(0);
    cout << fixed << setprecision(12);
    return 0;
}();

int n,k;
int a[N],b[N];

void solve() {
    cin>>n>>k;

    FOR(i,1,n)cin>>a[i];
    FOR(i,1,n)cin>>b[i];

    bool f=false;

    FOR(i,1,n){
        if(b[i]!=-1)f=1;
    }

    if(f){
        int x=-1;

        FOR(i,1,n){
            if(b[i]!=-1){
                if(x!=-1&&x!=b[i]+a[i]){
                    cout<<0<<endl;
                    RE;
                }
                if(x==-1)x=b[i]+a[i];
            }
        }

        FOR(i,1,n){
            if(b[i]==-1){
                if(x-a[i]>k||x-a[i]<0){
                    cout<<0<<endl;
                    RE;
                }
            }
        }

        cout<<1<<endl;
    }else{
        int t1=*min_element(a+1,a+1+n),t2=*max_element(a+1,a+1+n);
        int t=t2-t1;
        cout<<(k-t+1)<<endl;
    }

}

signed main() {
    int Task = 1;
    for (cin >> Task; Task; Task--) {
        solve();
    }
    return 0;
}